In the case of breast cancer, it’s thought that pregnancy causes breast tissue to become “fully matured,” according to Celia Byrne, Ph.D., an instructor of medicine at Harvard Medical School. “Until breast tissue reaches this stage, it may be more susceptible to potential cancer-causing insults from the environment,” Byrne says. Thus, the younger you are when you become pregnant, the sooner you’ll receive this pregnancy-related protection.

5. Stronger Bones: It’s possible that the added pounds of pregnancy may increase your bone density and reduce your risk of developing bone-weakening osteoporosis later in life, especially if you also take part in weight-bearing activities such as walking, Haas says. One caveat: Be sure to get plenty of calcium (at least 1,000 milligrams a day) and vitamin D (400 international units per day) throughout your pregnancy.

6. An Enduring Commitment to Healthful Habits: While you’re pregnant, you pay extra attention to your diet. You shun alcohol and caffeine, exercise moderately and regularly, take prenatal vitamins religiously and nap when you can. But as soon as you give birth, it’s time to go right back to your old, not-so-healthful ways, right? No way!

For some women, like Jane Kornbluh, 41, a childbirth educator and owner of Body by Baby, an infant/mother exercise company in Brooklyn, N.Y., such healthful habits turn out to have staying power. “I smoked for 20 years, but as soon as I got pregnant, I was thunderstruck with the absolute ridiculousness of it,” says Kornbluh, mother of 5-year-old Matteo. “I would never dream of smoking again.”

7. Closer Family Connections: Having children can make you more empathetic toward your parents. “You suddenly see what they gave up to raise you,” says therapist Fidell.

“I never realized how much my parents loved me until I had children myself,” says Kia Yelinek, 35, manager of a printing company in the Chicago area and mother of 3-year-old Alexander and 1-year-old Victoria. “Likewise, I’m so much more patient with my in-laws,” she says. Their unsolicited financial advice, for example, no longer bothers Yelinek because she now understands the concern behind their comments. “Before I became a parent, I thought, ‘Mind your own business,’” she says.

Motherhood can also change your relationships with other family members — particularly those who’ve given birth themselves, says Ann F. Caron, Ed.D., a psychologist in Greenwich, Conn. Once your baby is born, don’t be surprised if you feel more emotionally connected to your grandmother, as well as to aunts and cousins who are mothers. “There’s a bond that develops, something special between women who’ve experienced having a child,” Caron says.